Ares t.a.r. 21
 

So I've wanted on of these guns since it came out but since I read the review on it here I was hesitant about all of the work that would be needed on the gun to fix some basic problems

Then I found somebody selling one with a 6.03 MadBull barrel, KWA 2gx bucking, upgraded piston w/ alum head, deans connectors, and o-ring change

He says on the chrono its averaging about 360 fps.

I read that the nozzle leaks in the review on this site. Is it likely that the nozzle was replaced along with the piston, or if I replace the nozzle will I still gain fps seeing as to how its advertised fps is 350-380?

Also, has anybody found a fix for the super easy mag release?

Last but not least, will I be able to put the next grade up spring in so that it is shooting right under 400 fps? EDIT: without upgrading anything else?

Thanks